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source: vbox/trunk/src/libs/ffmpeg-20060710/libavformat/4xm.c@ 10184

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1/*
2 * 4X Technologies .4xm File Demuxer (no muxer)
3 * Copyright (c) 2003 The ffmpeg Project
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20/**
21 * @file 4xm.c
22 * 4X Technologies file demuxer
23 * by Mike Melanson ([email protected])
24 * for more information on the .4xm file format, visit:
25 * http://www.pcisys.net/~melanson/codecs/
26 */
27
28#include "avformat.h"
29
30#define RIFF_TAG MKTAG('R', 'I', 'F', 'F')
31#define _4XMV_TAG MKTAG('4', 'X', 'M', 'V')
32#define LIST_TAG MKTAG('L', 'I', 'S', 'T')
33#define HEAD_TAG MKTAG('H', 'E', 'A', 'D')
34#define TRK__TAG MKTAG('T', 'R', 'K', '_')
35#define MOVI_TAG MKTAG('M', 'O', 'V', 'I')
36#define VTRK_TAG MKTAG('V', 'T', 'R', 'K')
37#define STRK_TAG MKTAG('S', 'T', 'R', 'K')
38#define std__TAG MKTAG('s', 't', 'd', '_')
39#define name_TAG MKTAG('n', 'a', 'm', 'e')
40#define vtrk_TAG MKTAG('v', 't', 'r', 'k')
41#define strk_TAG MKTAG('s', 't', 'r', 'k')
42#define ifrm_TAG MKTAG('i', 'f', 'r', 'm')
43#define pfrm_TAG MKTAG('p', 'f', 'r', 'm')
44#define cfrm_TAG MKTAG('c', 'f', 'r', 'm')
45#define snd__TAG MKTAG('s', 'n', 'd', '_')
46
47#define vtrk_SIZE 0x44
48#define strk_SIZE 0x28
49
50#define GET_LIST_HEADER() \
51 fourcc_tag = get_le32(pb); \
52 size = get_le32(pb); \
53 if (fourcc_tag != LIST_TAG) \
54 return AVERROR_INVALIDDATA; \
55 fourcc_tag = get_le32(pb);
56
57typedef struct AudioTrack {
58 int sample_rate;
59 int bits;
60 int channels;
61 int stream_index;
62 int adpcm;
63} AudioTrack;
64
65typedef struct FourxmDemuxContext {
66 int width;
67 int height;
68 int video_stream_index;
69 int track_count;
70 AudioTrack *tracks;
71 int selected_track;
72
73 int64_t audio_pts;
74 int64_t video_pts;
75 float fps;
76} FourxmDemuxContext;
77
78static int fourxm_probe(AVProbeData *p)
79{
80 if (p->buf_size < 12)
81 return 0;
82
83 if ((LE_32(&p->buf[0]) != RIFF_TAG) ||
84 (LE_32(&p->buf[8]) != _4XMV_TAG))
85 return 0;
86
87 return AVPROBE_SCORE_MAX;
88}
89
90static int fourxm_read_header(AVFormatContext *s,
91 AVFormatParameters *ap)
92{
93 ByteIOContext *pb = &s->pb;
94 unsigned int fourcc_tag;
95 unsigned int size;
96 int header_size;
97 FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
98 unsigned char *header;
99 int i;
100 int current_track = -1;
101 AVStream *st;
102
103 fourxm->track_count = 0;
104 fourxm->tracks = NULL;
105 fourxm->selected_track = 0;
106 fourxm->fps = 1.0;
107
108 /* skip the first 3 32-bit numbers */
109 url_fseek(pb, 12, SEEK_CUR);
110
111 /* check for LIST-HEAD */
112 GET_LIST_HEADER();
113 header_size = size - 4;
114 if (fourcc_tag != HEAD_TAG)
115 return AVERROR_INVALIDDATA;
116
117 /* allocate space for the header and load the whole thing */
118 header = av_malloc(header_size);
119 if (!header)
120 return AVERROR_NOMEM;
121 if (get_buffer(pb, header, header_size) != header_size)
122 return AVERROR_IO;
123
124 /* take the lazy approach and search for any and all vtrk and strk chunks */
125 for (i = 0; i < header_size - 8; i++) {
126 fourcc_tag = LE_32(&header[i]);
127 size = LE_32(&header[i + 4]);
128
129 if (fourcc_tag == std__TAG) {
130 fourxm->fps = av_int2flt(LE_32(&header[i + 12]));
131 } else if (fourcc_tag == vtrk_TAG) {
132 /* check that there is enough data */
133 if (size != vtrk_SIZE) {
134 av_free(header);
135 return AVERROR_INVALIDDATA;
136 }
137 fourxm->width = LE_32(&header[i + 36]);
138 fourxm->height = LE_32(&header[i + 40]);
139 i += 8 + size;
140
141 /* allocate a new AVStream */
142 st = av_new_stream(s, 0);
143 if (!st)
144 return AVERROR_NOMEM;
145 av_set_pts_info(st, 60, 1, fourxm->fps);
146
147 fourxm->video_stream_index = st->index;
148
149 st->codec->codec_type = CODEC_TYPE_VIDEO;
150 st->codec->codec_id = CODEC_ID_4XM;
151 st->codec->codec_tag = 0; /* no fourcc */
152 st->codec->width = fourxm->width;
153 st->codec->height = fourxm->height;
154
155 } else if (fourcc_tag == strk_TAG) {
156 /* check that there is enough data */
157 if (size != strk_SIZE) {
158 av_free(header);
159 return AVERROR_INVALIDDATA;
160 }
161 current_track = LE_32(&header[i + 8]);
162 if (current_track + 1 > fourxm->track_count) {
163 fourxm->track_count = current_track + 1;
164 if((unsigned)fourxm->track_count >= UINT_MAX / sizeof(AudioTrack))
165 return -1;
166 fourxm->tracks = av_realloc(fourxm->tracks,
167 fourxm->track_count * sizeof(AudioTrack));
168 if (!fourxm->tracks) {
169 av_free(header);
170 return AVERROR_NOMEM;
171 }
172 }
173 fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
174 fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
175 fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
176 fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
177 i += 8 + size;
178
179 /* allocate a new AVStream */
180 st = av_new_stream(s, current_track);
181 if (!st)
182 return AVERROR_NOMEM;
183
184 av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
185
186 fourxm->tracks[current_track].stream_index = st->index;
187
188 st->codec->codec_type = CODEC_TYPE_AUDIO;
189 st->codec->codec_tag = 1;
190 st->codec->channels = fourxm->tracks[current_track].channels;
191 st->codec->sample_rate = fourxm->tracks[current_track].sample_rate;
192 st->codec->bits_per_sample = fourxm->tracks[current_track].bits;
193 st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
194 st->codec->bits_per_sample;
195 st->codec->block_align = st->codec->channels * st->codec->bits_per_sample;
196 if (fourxm->tracks[current_track].adpcm)
197 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
198 else if (st->codec->bits_per_sample == 8)
199 st->codec->codec_id = CODEC_ID_PCM_U8;
200 else
201 st->codec->codec_id = CODEC_ID_PCM_S16LE;
202 }
203 }
204
205 av_free(header);
206
207 /* skip over the LIST-MOVI chunk (which is where the stream should be */
208 GET_LIST_HEADER();
209 if (fourcc_tag != MOVI_TAG)
210 return AVERROR_INVALIDDATA;
211
212 /* initialize context members */
213 fourxm->video_pts = -1; /* first frame will push to 0 */
214 fourxm->audio_pts = 0;
215
216 return 0;
217}
218
219static int fourxm_read_packet(AVFormatContext *s,
220 AVPacket *pkt)
221{
222 FourxmDemuxContext *fourxm = s->priv_data;
223 ByteIOContext *pb = &s->pb;
224 unsigned int fourcc_tag;
225 unsigned int size, out_size;
226 int ret = 0;
227 int track_number;
228 int packet_read = 0;
229 unsigned char header[8];
230 int audio_frame_count;
231
232 while (!packet_read) {
233
234 if ((ret = get_buffer(&s->pb, header, 8)) < 0)
235 return ret;
236 fourcc_tag = LE_32(&header[0]);
237 size = LE_32(&header[4]);
238 if (url_feof(pb))
239 return AVERROR_IO;
240 switch (fourcc_tag) {
241
242 case LIST_TAG:
243 /* this is a good time to bump the video pts */
244 fourxm->video_pts ++;
245
246 /* skip the LIST-* tag and move on to the next fourcc */
247 get_le32(pb);
248 break;
249
250 case ifrm_TAG:
251 case pfrm_TAG:
252 case cfrm_TAG:{
253
254 /* allocate 8 more bytes than 'size' to account for fourcc
255 * and size */
256 if (size + 8 < size || av_new_packet(pkt, size + 8))
257 return AVERROR_IO;
258 pkt->stream_index = fourxm->video_stream_index;
259 pkt->pts = fourxm->video_pts;
260 pkt->pos = url_ftell(&s->pb);
261 memcpy(pkt->data, header, 8);
262 ret = get_buffer(&s->pb, &pkt->data[8], size);
263
264 if (ret < 0)
265 av_free_packet(pkt);
266 else
267 packet_read = 1;
268 break;
269 }
270
271 case snd__TAG:
272 track_number = get_le32(pb);
273 out_size= get_le32(pb);
274 size-=8;
275
276 if (track_number == fourxm->selected_track) {
277 ret= av_get_packet(&s->pb, pkt, size);
278 if(ret<0)
279 return AVERROR_IO;
280 pkt->stream_index =
281 fourxm->tracks[fourxm->selected_track].stream_index;
282 pkt->pts = fourxm->audio_pts;
283 packet_read = 1;
284
285 /* pts accounting */
286 audio_frame_count = size;
287 if (fourxm->tracks[fourxm->selected_track].adpcm)
288 audio_frame_count -=
289 2 * (fourxm->tracks[fourxm->selected_track].channels);
290 audio_frame_count /=
291 fourxm->tracks[fourxm->selected_track].channels;
292 if (fourxm->tracks[fourxm->selected_track].adpcm)
293 audio_frame_count *= 2;
294 else
295 audio_frame_count /=
296 (fourxm->tracks[fourxm->selected_track].bits / 8);
297 fourxm->audio_pts += audio_frame_count;
298
299 } else {
300 url_fseek(pb, size, SEEK_CUR);
301 }
302 break;
303
304 default:
305 url_fseek(pb, size, SEEK_CUR);
306 break;
307 }
308 }
309 return ret;
310}
311
312static int fourxm_read_close(AVFormatContext *s)
313{
314 FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
315
316 av_free(fourxm->tracks);
317
318 return 0;
319}
320
321static AVInputFormat fourxm_demuxer = {
322 "4xm",
323 "4X Technologies format",
324 sizeof(FourxmDemuxContext),
325 fourxm_probe,
326 fourxm_read_header,
327 fourxm_read_packet,
328 fourxm_read_close,
329};
330
331int fourxm_init(void)
332{
333 av_register_input_format(&fourxm_demuxer);
334 return 0;
335}
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